Coating composition comprising fluorochemical polyether silane polycondensate and use thereof

ABSTRACT

A composition comprising the condensation product of a least one fluorochemical polyether silane compound having a polyfluoropolyether segment and at least two hydrolysable silane groups per molecule, with one or more non-fluorinated compounds having at least two hydrolysable groups per molecule, and the reaction product thereof, is disclosed. The composition provides durable water, oil and stain repellency to a substrate.

The present invention relates to a composition comprising thecondensation product of at least one fluorochemical polyether silanecompound having a polyfluoropolyether segment and at least twohydrolysable silane groups per molecule with one or more non-fluorinatedcompounds having at least two hydrolysable groups per molecule. Thepresent invention also relates to the use of the composition forproviding durable repellency to water, oil and stain to a substrate.

In the past, various efforts have been made to provide repellentproperties to a substrate. For example, U.S. Pat. No. 4,687,707 (=EP-A-0166 363) describes a low reflectance, transparent material havinganti-soiling properties, which comprises a transparent substrate havinga coating comprising a thin layer of a condensation product of afluorine containing silicon compound having a polyfluorinated orperfluorinated carbon chain.

WO 99/03941 relates to a coating material comprising condensates of atleast one compound (A) of the general formula R_(a)MZ_(b) (a=0 to 3; b=1to 4; a+b=3, 4), and at least one compound (B) of the general formulaR′_(x)MZ_(y) (x=1 to 3; y=1 to 3; x+y=3,4), wherein R is anon-hydrolysable organic group, M is an element selected from the maingroups III to V or from the subgroups II to IV of the periodic table ofelements, Z is a hydrolysable group, and at least one R′ contains aperfluoropolyether structure separated from M by at least two atoms, andat least one R is not equal to at least one R′. The composition is usedto provide oleophobic properties to substrates, such as porous polymers.

U.S. Pat. No. 5,739,369 (=EP-A-0 738 771) relates to a water-solublesurface treating agent comprising the reaction product of (A) afluoroalkyl group-containing alkoxysilane with (B) anamino-group-containing alkoxysilane and optionally further with (C) analkyl group-containing alkoxysilane. The agent is diluted with water toform a solution for treating glass and other substrates to impartthereto properties, such as water repellency.

U.S Pat. No. 5,919,886 relates to a fluorine-containing organo-siliconcompound useful for obtaining elastomers and to room temperature curablesilicon compositions containing the same compound.

U.S. Pat. No. 5,306,758 (=EP-A-0 433 070) describes fluorocarbon based,curable, crosslinkable compositions and coatings prepared therefrom thatcan be used to form low-surface energy release liners.

U.S. Pat. No. 5,922,787 (=EP-0 797 111) relates to a compositioncontaining an alkoxy-silane compound having a perfluoropolyether group.The composition may be used for forming an anti-fouling film.

However, our findings indicate that while some of the previously knownsurface coatings may be capable of providing acceptable levels ofinitial repellent properties, a loss of repellency is often encountereddue to abrasion of the coating. Also, if non-fluorine containingcomponents are additionally employed in the coating composition, astep-wise hydrolysis is often required (see for example U.S. Pat. No.5,644,014), wherein in a first step a precondensation of thenon-fluorinated silane is carried out and only subsequently thefluorinated silane compound may be added. If a one-step hydrolysis iscarried out, often phase separation occurs thereby leading tonon-homogenous coatings having insufficient repellent properties.

Accordingly, it is desirable to provide a coating composition capable ofproviding a highly durable water, oil and/or stain repellent coating ona substrate. In particular, it is desirable to provide a durable coatingwherein the initial, repellent properties are substantially maintained,even under abrading conditions. Further, the coating compositionspreferably can be applied and used in an environmental friendly way andcan be produced in a reliable, convenient and cost effective way.

SUMMARY OF THE INVENTION

In one aspect, the present invention provides a composition comprisingthe reaction product obtainable after a substantially completecondensation reaction of (A) one or more fluorochemical polyether silanecompound(s) having a polyfluoropolyether segment and at least two silanegroups —Si(Y)_(3−x)(R¹)_(x) per molecule, wherein R¹ represents an alkylgroup, Y represents a hydrolysable group and x is 0 or 1; and (B) asubstantial amount of one or more non-fluorinated compounds of anelement M selected from the group consisting of Si, Ti, Zr, B, Al, Ge,V, Pb, Sn and Zn and having at least two hydrolysable groups permolecule. By the term “substantially complete condensation reaction” ismeant that the reaction is either complete or at least 80% of thehydrolysable groups in the mixture have disappeared, preferably at least90%. Completion of the reaction can be monitored through the use ofinfrared spectroscopy and C¹³—NMR.

In a further aspect, the present invention provides a method forpreparation of the condensation product. In a still further aspect, thepresent invention also provides a method for treating a substrate,comprising the step of applying to the substrate the composition asdefined above. The fluorochemical compositions can be used to treatsubstrates and are capable of rendering such substrates oil and waterrepellent and/or to provide stain repellency thereto.

The compositions are generally effective at low levels of applicationand have good durability. The compositions are particularly useful forrendering substrates such as ceramics, metal, polymeric substrates andglass repellent to water and/or oil.

In one embodiment, a homogeneous reaction product mixture can beobtained by simply mixing the components in a suitable solvent, in thepresence of reagent water, and optionally of a catalyst. There is noneed for a two-step reaction; where in a first step a precondensate ofcompound (B) is formed and in a second step, the fluorochemicalpolyether disilane (A) is added. Accordingly, the reaction product ofthe invention can be produced in an easy and reliable way.

By the term “homogeneous mixture” in connection with the presentinvention is meant that the composition is stable, for at least 24hours, preferably 1 month, at room temperature. Some haziness may occur,however without substantial precipitation or phase separation occurring.

The term “hydrolysable group” in connection with the present inventionrefers to a group which either is directly capable of undergoingcondensation reactions under appropriate conditions or which is capableof hydrolyzing under appropriate conditions, thereby yielding acompound, which is capable of undergoing condensation reactions.Appropriate conditions include acidic or basic aqueous conditions,optionally in the presence of a condensation catalyst.

Accordingly, the term “non-hydrolysable group” as used in the presentinvention refers to a group not capable of either directly undergoingcondensation reactions under appropriate conditions or of hydrolyzingunder the conditions listed above for hydrolyzing the hydrolyzablegroups.

The term “substantial amount” of a compound as used herein refers to anamount of a compound greater than a catalytic amount of that compoundnecessary for promoting a certain reaction (e.g., condensationreactions). Accordingly, a composition comprising a substantial amountof that compound generally allows the compound to act as a reactant suchthat the resulting product is formed of at least part of that compound.

DETAILED DESCRIPTION

Component (A) comprises at least one fluorochemical polyether silanecompound having a polyfluoropolyether segment and at least two silanegroups —Si(Y)_(3−x)(R¹)_(x) per molecule, wherein R¹ represents an alkylgroup (for example a C₁-C₈, preferably C₁-C₄ primary or secondary alkylgroup), Y represents a hydrolysable group and x is 0 or 1.

Preferably, component (A) is a fluorochemical polyether silane compoundaccording to formula (I)

R_(f)[Q—C(R)₂—Si(Y)_(3−x)(R¹)_(x)]_(z)  (I)

wherein R_(f) represents a multivalent polyfluoropolyether segment, Qrepresents an organic divalent linking group, R¹ represents an alkylgroup (preferably containing 1 to 8, more preferably 1 to 4 carbonatoms), Y represents a hydrolysable group; R represents hydrogen or analkyl group of 1 to 4 carbon atoms and the R groups may be the same ordifferent, x is 0 or 1 and z is 2, 3 or 4. Preferably both R groups arehydrogens.

The hydrolysable groups Y may be the same or different and are generallycapable of hydrolyzing under appropriate conditions, for example underacidic or basic aqueous conditions, such that the fluorochemical silanecompound can then undergo condensation reactions. Preferably, thehydrolysable groups upon hydrolysis yield groups capable of undergoingcondensation reactions, such as silanol groups.

Examples of hydrolysable groups include halide groups, such as chlorine,bromine, iodine or fluorine, alkoxy groups —OR′ (wherein R′ represents alower alkyl group, preferably containing 1 to 6, more preferably 1 to 4carbon atoms and which may optionally be substituted by one or morehalogen atoms), acyloxy groups —O(CO)—R″ (wherein R″ represents a loweralkyl group, preferably containing 1 to 6, more preferably 1 to 4 carbonatoms, which may be optionally substituted by one or more halogenatoms), aryloxy groups —OR′″ (wherein R′″ represents an aryl moiety,preferably containing 6 to 12, more preferably containing 6 to 10 carbonatoms, which may be optionally substituted by one or more substituentsindependently selected from halogens, and C₁-C₄ alkyl groups which mayoptionally be substituted by one or more halogen atoms). In the aboveformulae R′, R″, and R′″ may include branched structures.

Suitable hydrolysable groups also include polyoxyalkylene groups of theformula

—O—A—R³

wherein A is a divalent hydrophilic group (a) having the formula

(CHR⁴—CH₂O—)_(q)

wherein q is a number having a value of 1 to 40, preferably 2 to 10, R⁴is hydrogen or methyl, and at least 70% of R⁴ is hydrogen, and R³independently is hydrogen or a lower alkyl group having 1 to 4 carbonatoms, such as disclosed in U.S. Pat. No. 5,274,159, incorporated hereinby reference.

Specific examples of hydrolysable groups include methoxy, ethoxy andpropoxy groups, chlorine and an acetoxy group. Particularly preferredhydrolysable groups include C₁-C₄ alkoxy groups, such as methoxy andethoxy groups.

The divalent polyfluoropolyether group R_(f) in the above formula (I),representing the fluorinated polyether silane, can include linear,branched, and/or cyclic structures, that may be saturated orunsaturated, and containing one or more caternary oxygen atoms (i.e. oneor more non-adjacent —CF₂— groups may be replaced by —O— groups). R_(f)preferably is a perfluorinated group (i.e., all C—H bonds are replacedby C—F bonds). More preferably, it includes perfluorinated repeatingunits selected from the group of —(C_(n)F_(2n)O)—, —(CF(Z)O)—,—(CF(Z)C_(n)F_(2n)O)—, —(C_(n)F_(2n)CF(Z)O)—, —(CF₂CF(Z)O)—, andcombinations thereof, wherein the repeating units generally may berandomly, blocky or alternating arranged, and optionally can include—(C_(n)F_(2n))— and —(CF(Z))— units and wherein n in a number from 1 to12 inclusive, preferably from 1 to 4 inclusive. R_(f) may also comprisecyclic perfluoro groups, for example cyclic —C₆F₁₀— groups.

In these repeating units Z is a perfluoroalkyl group, an oxygen-containing perfluoroalkyl group, a perfluoroalkoxy group, or anoxygen-substituted perfluoroalkoxy group, all of which can be linear,branched, or cyclic, and preferably have about 1 to about 9 carbon atomsand 0 to about 4 oxygen atoms. Examples of polyfluoropolyetherscontaining polymeric moieties made of these repeating units aredisclosed in U.S. Pat. No. 5,306,758 (Pellerite).

In one embodiment, approximate average structures for a divalentperfluoropolyether group include —CF₂O(CF₂O)_(m)(C₂F₄O)_(p)CF₂—, whereinan average value for m is 0 to about 50 and an average value for p is 0to about 50, with the proviso that both m and p are not simultaneously0, —CF(CF₃)—(OCF₂CF(CF₃))_(p)O—R_(f)′—O(CF(CF₃)CF₂O)_(p)CF(CF₃)—,—CF₂O(C₂F₄O)_(p)CF₂—, and —(CF₂)₃O(C₄F₈O)_(p)(CF₂)₃—, wherein R_(f)′ isa divalent, perfluoroalkylene group containing one or more carbons andoptionally catenary O or N. The values of m and p in these approximateaverage structures can vary. Preferably, an average value of m is withina range of about 1 to about 50, and an average value of p is within arange of about 3 to about 40. As these are polymeric materials, suchcompounds exist as mixtures upon synthesis, which are suitable for use.The repeat units generally may be positioned in a random, blocked oralternating arrangement.

As synthesized, these structures typically include a mixture ofpolymeric units. The approximate average structure is the approximateaverage of the mixture of structures. Further, the distribution ofperfluorinated repeating units may be regular or random.

The divalent linking group Q may be the same or different and caninclude linear, branched, or cyclic structures, that may be saturated orunsaturated, and preferably contains 1 to 15 atoms. The group Q cancontain one or more heteroatoms (e.g., oxygen, nitrogen, or sulfur)and/or one or more functional groups (e.g., carbonyl, amide, urethane orsulfonamide). It can also be substituted with one or more halogen atoms(preferably, fluorine atoms), although this is less desirable, as thismight lead to instability of the compound. The divalent linking group Qpreferably is substantially stable against hydrolysis.

For example, Q may be a saturated or unsaturated hydrocarbon grouptypically including 1 to 15 carbons atoms. Preferably Q is a linearhydrocarbon group preferably containing 1 to 10 carbon atoms, andoptionally containing 1 to 4 heteroatoms and/or 1 to 4 functionalgroups, and more preferably, containing at least one functional group.

Suitable linking groups Q include the following structures in additionto a covalent bond. For the purposes of this list, each k isindependently an integer from 0 to about 20, k′ is independently aninteger from 0 to 20, preferably from 2 to 12 and most preferably from 2to 6, R₁′ is hydrogen, phenyl, or alkyl of 1 to about 4 carbon atoms,and R₂′ is alkyl of 1 to about 20 carbon atoms

—SO₂NR₁′(CH₂)_(k)O(O)C— —CONR₁′(CH₂)_(k)O(O)C— —(CH₂)_(k)O(O)C——CH₂CH(OR₂′)CH₂O(O)C— —(CH₂)_(k)C(O)O(CH₂)_(k)— —(CH₂)_(k)SC(O)——(CH₂)_(k)O(CH₂)_(k)O(O)C— —(CH₂)_(k)S(CH₂)_(k)O(O)C——(CH₂)_(k)SO₂(CH₂)_(k)O(O)CH₃ —(CH₂)_(k)S(CH₂)_(k)OC(O)——(CH₂)_(k)SO₂NR₁′(CH₂)_(k)O(O)C— —(CH₂)_(k)SO₂——SO₂NR₁′(CH₂)_(k)O(CH₂)_(k′)— —SO₂NR₁′(CH₂)_(k)——(CH₂)_(k)O(CH₂)_(k)C(O)O(CH₂)_(k′)——(CH₂)_(k)SO₂NR₁′(CH₂)_(k)C(O)O(CH₂)_(k′)——(CH₂)_(k)SO₂(CH₂)_(k)C(O)O(CH₂)_(k′)— —CONR₁′(CH₂)_(k)C(O)O(CH₂)_(k′)——(CH₂)_(k)S(CH₂)_(k)C(O)O(CH₂)_(k′)— —CH₂CH(OR₂′)CH₂C(O)O(CH₂)_(k′)——SO₂NR₁′(CH₂)_(k)C(O)O(CH₂)_(k′)— —(CH₂)_(k)O(CH₂)_(k′)——OC(O)NR′(CH₂)_(k)— —(CH₂)_(k)NR₁′- —C_(k)H_(2k)—OC(O)NH——C_(k)H_(2k)—NR₁′C(O)NH(CH₂)_(k′)—, —(CH₂)_(k)NR₁′C(O)O(CH₂)_(k′)—, and—(CH₂)_(k)—

Preferred linking groups Q are —C(O)NH(CH₂)₂— and —OC(O)NH(CH₂)₂—.

Conveniently, the compounds of formula I used, generally have an averagemolecular weight of at least about 650, and preferably, at least about1000. It will be understood, with respect to the description of formulaI, that the composition comprises mixtures of compounds and thereforemixtures of molecular weights.

Examples of preferred fluorinated disilanes include, but are not limitedto, the following approximate average structures:

(R¹)_(x)(Y)_(3−x)Si—CR₂—QCF₂O(CF₂O)_(m)(C₂F₄O)_(p)CF₂Q—CR₂—Si(Y)_(3−x)(R¹)_(x),

(R¹)_(x)(Y)_(3−x)Si—CR₂—QCF(CF₃)O[CF₂CF(CF₃)]_(m)(CF₂)_(p)O[CF(CF₃)CF₂O]_(n)CF(CH₃)Q—CR₂—Si(Y)_(3−x)(R¹)_(x)

(R¹)_(x)(Y)_(3−x)Si—CR₂—QCF₂O(C₂F₄O)_(p)CF₂Q—CR₂—Si(Y)_(3−x)(R¹)_(x),and

(R¹)_(x)(Y)_(3−x)Si—CR₂—Q(CF₂)₃O(C₄F₈O)_(p)(CF₂)₃Q—CR₂—Si(Y)_(3−x)(R¹)_(x),

Preferably, in each fluorinated polyether silane, Q contains a nitrogenatom. More preferably, at least one Q—CR₂—Si(Y)_(3−x)(R¹)_(x) group permolecule is —C(O)NH(CH₂)₃Si(OR)₃ or —OC(O)NH(CH₂)₃Si(OR)₃ (wherein R ismethyl, ethyl, polyethyleneoxy or mixtures thereof).

The compounds of formula (I) can be synthesized using standardtechniques. For example, commercially available or readily synthesizedperfluoropolyether esters (or function derivative thereof) can becombined with a functionalized alkoxysilane, such as a3-aminopropylalkoxysilane, according to U.S. Pat. No. 3,810,874 (Mitschet al.). It will be understood that functional groups other than estersmay be used with equal facility to incorporate silane groups into aperfluoropolyether.

In accordance with a particular embodiment of the present invention,such perfluoropolyether diesters may be prepared through directfluorination of a hydrocarbon polyether diester. Direct fluorinationinvolves contacting the hydrocarbon polyether diester with F₂.Accordingly, the hydrogen atoms on the hydrocarbon polyether diesterwill be replaced with fluorine atoms thereby generally resulting in thecorresponding perfluoropolyether diester. Direct fluorination methodsare disclosed in, for example, U.S. Pat. Nos. 5,578,278 and 5,658,962,which are incorporated herein by reference.

Examples of intermediates suitable for use in the preparation offluorochemical polyether silanes may be represented by the generalformula R_(f)—X_(z), wherein R_(f) is as previously defined for FormulaI and z is 2, 3 or 4. A particularly useful intermediate may berepresented by the general formula

X(CF₂)_(n)—O—C_(n′)F_(2n′)—O—(CF₂)_(n)X

where n is in the range of 1 to 6, and preferably in the range of 1 to3; n′ is in the range of 5 to 12, and preferably in the range of 5 to 7,X is selected from the group consisting of —COOH, —COOM_(1/v), —COONH₄,—COOR, —CH₂OH, —COF, —COCl, —COR, CONR′R′, —CH₂NH₂, —CH₂NCO, —CN,—CH₂OSO₂R, —CH₂OCOR, —OC(O)CH₃, —CH₂OCOCR′═CH₂, —CONH(CH₂)_(m)Si(OR)₃,and —CH₂O(CH₂)_(m)Si(OR)₃;

where M is a metal atom having a valence “v” of 1 to 4, each R isindependently selected from the group consisting of alkyl groups havingfrom 1 to 14 carbon atoms, fluoroalkyl groups having from 1 to 14 carbonatoms, aryl groups having from 6 to 10 ring-carbon atoms, andheteroatom-containing groups having from 1 to 14 carbon atoms, and m isan integer in the range from 1 to 11; R′ is independently H or R withthe proviso R′ is not a fluoroalkyl group.

Specific structures are exemplified by:

It will be understood with respect to the above novel structures, thatother functional groups may be substituted for those depicted. Forexamples, the —CO₂H group may be substituted by —COOM_(1/v), —COONH₄,—COOR, —CH₂OH, —COF, —COCl, —COR, CONR′R′, —CH₂NH₂, —CH₂NCO, —CN,—CH₂OSO₂R, —CH₂OCOR, —OC(O)CH₃, —CH₂OCOCR′═CH₂, —CONH(CH₂)_(m)Si(OR)₃,and —CH₂O(CH₂)_(m)Si(OR)₃ as previously described.

An additional embodiment is a composition comprising

X(CF₂)_(n)—O—(CF₂)_(q)—(C_(n′)F_(2n′−2))—(CF₂)_(q)—O—(CF₂)_(n)X

where n is in the range of 1 to 6, and preferably in the range of 1 to3; C_(n′)F_(2n′−2) represents a cycloalkylene moiety where n′ is in therange of 5 to 12, and preferably in the range of 6 to 8, X is selectedfrom the group consisting of —COOH, —COOM_(1/v), —COONH₄, —COOR, —CH₂OH,—COF, —COCl, —COR′, CONR′R′, —CH₂NH₂, —CH₂NCO, —CN, —CH₂OSO₂R, —CH₂OCOR,—OC(O)CH₃, —CH₂OCOCR′═CH₂, —CONH(CH₂)_(m)Si(OR)₃, —CH₂O(CH₂)_(m)Si(OR)₃;where M is a metal atom having a valence “v” of 1 to 4, each R isindependently selected from the group consisting of alkyl groups havingfrom 1 to 14 carbon atoms, fluoroalkyl groups having from 1 to 14 carbonatoms, aryl groups having from 6 to 10 ring-carbon atoms, andheteroatom-containing groups having from 1 to 14 carbon atoms, q is 0 or1, and m is an integer in the range from 1 to 11; R′ is independently Hor R with the proviso R′ is not a fluoroalkyl group.

Specific perfluorinated cycloalkylene-containing structures areexemplified by:

In an alternative method, perfluoropolyetherdiols can be reacted with afunctionalized alkoxysilane, such as 3-trimethoxysilylpropylisocyanate.Modifications of this method are described in the Examples. Suchmaterials may or may not need to be purified before use in a treatmentcomposition.

In the present invention, mixtures of compounds (A) and/or (B) may beused.

Component (B) as used in the present invention comprises one or morenon-fluorinated compounds of an element M selected from the groupconsisting of Si, Ti, Zr, B, Al, Ge, V, Pb, Sn and Zn having at leasttwo hydrolysable groups per molecule. Preferably, the hydrolysablegroups are directly bonded to the element M.

In one embodiment of the present invention, component (B) comprises acompound according to the formula (II)

(R²)_(q)M(Y¹)_(p−q)  (II)

wherein R² represents a non-hydrolysable group, M represents an elementof valency p+q, selected from the group consisting of Si, Ti, Zr, B, Al,Ge, V, Pb, Sn and Zn, p is 3 or 4 depending on the valence of M, q is0,1 or 2, and Y¹ represents a hydrolysable group.

The hydrolysable groups present in component (B) may be the same ordifferent and are generally capable of hydrolyzing under appropriateconditions, for example under acidic or basic aqueous conditions, suchthat component (B) can undergo condensation reactions. Preferably, thehydrolysable groups upon hydrolysis yield groups capable of undergoingcondensation reactions, such as hydroxyl groups.

Typical and preferred examples of hydrolysable groups include those asdescribed with respect to component (A). Preferably, component (B)includes tetra-, tri- or dialkoxy (preferably containing 1 to 4 carbonatoms) compounds.

The non-hydrolysable groups R² may be the same or different and aregenerally not capable of hydrolyzing under the conditions listed above.For example, the non-hydrolysable groups R² may be independentlyselected from a hydrocarbon group, for example a C₁-C₃₀ alkyl group,which may be straight chained or branched and may include one or morealiphatic, cyclic hydrocarbon structures, a C₆-C₃₀ aryl group(optionally substituted by one or more substituents selected fromhalogens and C₁-C₄ alkyl groups), or a C₇-C₃₀ aralkyl group.

In one embodiment the non-hydrolysable groups R² are independentlyselected from a hydrocarbon group, for example a C₁-C₃₀ alkyl group anda C₆-C₂₀ aryl group (optionally substituted by one or more substituentsselected from halogens and C₁-C₄ alkyl groups).

Preferred compounds (B) include those in which M is Ti, Zr, Si and Al.Representative examples of component (B) include tetramethoxysilane,tetra ethoxysilane, methyl triethoxysilane, dimethyldiethoxysilane,octadecyltriethoxysilane, methyl trichlorosilane, tetra-methylorthotitanate, tetra ethyl orthotitanate, tetra-iso-propylorthotitanate, tetra-n-propyl orthotitanate, tetraethyl zirconate,tetra-iso-propyl zirconate tetra-n-propyl zirconate and the like. Morepreferred compounds include C₁-C₄ alkoxy derivatives of Si, Ti and Zr.Particularly preferred compounds (B) include tetraethoxysilane. Singlecompounds or mixtures of compounds (B) may be used.

Optionally, the composition may comprise one or more crosslinking agents(C), in order to further increase the durability of the coating.Component (C) may be selected from compounds with additionalfunctionality from those of components (A) and (B). For example,component (C) may comprise a compound of an element M¹ that is selectedfrom the group consisting of Si, Ti, Zr, B, Al, Ge, V, Pb, Sn and Znhaving at least one hydrolysable group and at least one reactivefunctional group per molecule that is capable of engaging in acrosslinking reaction. Preferably, said at least one hydrolysable groupis directly bonded to the element M¹.

Suitable and preferred hydrolysable groups include those groupsmentioned with respect to component (A). If component (C) includes morethan one hydrolysable groups, these may be the same or different.Particularly preferred hydrolysable groups are selected from C₁-C₄alkoxy groups, such as methoxy, ethoxy, iso- and (preferably) n-propoxy,or iso- and (preferably) n-butoxy groups.

The reactive functional group is a group which is capable of engaging ina crosslinking reaction so as to provide further crosslinkingfunctionality to the polycondensation product that can be obtained fromcomponents (A), (B) and (C). The crosslinking reaction may involve forexample irradiation, heating or a combination thereof. If component (C)includes more than one reactive functional groups, these groups may bethe same or different. Of these, free radically polymerizable groups,such as vinyl, acrylate or methacrylate groups, are particularlypreferred reactive functional groups.

A preferred crosslinking agent can be represented by formula (IV):

L—Q—Si(Y)_(3−x)(R¹)_(x)

wherein

L represents a reactive functional group that may react by condensationor addition reactions such as an amino group, an epoxy group, amercaptan or an anhydride group or by free-radical polymerization; and

Q, Y and R¹ are as described for formula I, and x is 0, 1 or 2.

For formula V, preferably Q is an alkylene (preferably containing 1 to10, more preferably containing 1 to 6 carbon atoms), an arylene(preferably containing 6 to 20 carbon atoms which may be substituted byone or more C₁-C₄ alkyl groups, halogen atoms or mixtures thereof), anoxyalkylene group of the formula (—O—R—)_(n), wherein R is independentlyselected from a divalent, straight chained or branched lower alkyl group(preferably containing 1 to 6 carbon atoms) and n is an integer from 1to 20.

For formula IV, preferably R¹ independently represents an alkyl group,preferably a C₁-C₈ alkyl group (such as methyl, ethyl or propyl) or anC₁-C₈ alkyl group containing a cyclic hydrocarbon structure (such ascycloalkyl such as cyclohexyl or cyclopentyl), an aryl group (preferablycontaining 6 to 20 carbon atoms which may optionally be substituted byone or more C₁-C₄ alkyl groups or halogens or mixtures thereof, such asphenyl), an alkylaryl group (preferably containing 7 to 12 carbon atoms)or an aralkyl group (preferably containing 7 to 12 carbon atoms).

For formula IV, Y is hydrolysable group. Suitable and preferred examplesof hydrolysable groups include those groups as mentioned with respect tocomponent (A), formula I. Particularly preferred hydrolysable groupsinclude alkoxy groups (preferably containing 1 to 4 carbon atoms), suchas methoxy and ethoxy groups.

Particularly preferred reactive compounds according to formula (IV), inwhich the reactive functional group L is one that reacts by addition orcondensation reactions, include epoxypropyltrimethoxysilane,bis(3-aminopropyltrimethoxysilyl)amine and aminopropyltrimethoxysilane.

Alternatively L may be a reactive functional group that is a freeradically polymerizable group that typically contains an ethylenicallyunsaturated group capable of undergoing a free radical polymerization.Suitable free radically polymerizable groups L include, for example,moieties derived from vinyl ethers, viniyl esters, allyl esters, vinylketones, styrene, vinyl amide, acrylamides, maleates, fumarates,acrylates and methacrylates. Of these, the esters and amides of alpha,beta unsaturated acids, such as the acrylates and methacrylates arepreferred.

Where L is a free radically polymerizable group the organic divalentlinking group Q may contain from 1 to about 20, preferably from 1 to 10carbon atoms. Q can optionally contain oxygen, nitrogen, orsulfur-containing groups or a combination thereof. Examples of suitablelinking groups Q include straight chain, branched chain or cyclicalkylene (preferably containing 2 to 20 carbon atoms), arylene(preferably containing 6 to 20 carbon atoms), aralkylene (preferablycontaining 7 to 20 carbon atoms), oxyalkylene, carbonyloxyalkylene,oxycarboxyalkylene, carboxyamidoalkylene, urethanylenealkylene,ureylenealkylene and combinations thereof.

Preferred linking groups Q for Formula IV are selected from the groupconsisting of alkylene (preferably containing 2 to 20, more preferably 2to 10 carbon atoms), oxyalkylene (preferably containing 2 to 20 carbonatoms and 1 to 10 oxygen atoms) and carbonyloxyalkylene (preferablycontaining 3 to 20 carbon atoms).

Examples of compounds according to formula (IV), wherein L is a freeradically polymerizable group include vinyltrichlorosilane,vinyltrimethoxysilane, vinyltriethoxysilane and alkoxysilanefunctionalised acrylates or methacrylates, such as methacryloyloxypropyltrimethoxysilane.

The presence of such reactive functional groups, preferably reactiveunsaturated groups in the corresponding polycondensates is advantageousin that following the coating of the composition onto a substrate atwo-fold curing can be carried out, i.e. a thermal or photochemicallyinduced linking of the unsaturated organic radicals through radicalpolymerization and a thermal completion of the polycondensation (e.g. byelimination of water from groups M—OH still present). In the case anunsaturated compound is used, additionally a catalyst should typicallybe present for the thermal and/or photochemically induced curing of thecoating composition applied onto a suitable substrate. Particularlypreferred is the addition of a photopolymerization initiator. Suchinitiators are commercially available and include e.g. Irgacure® 184(1-hydroxycyclohexyl phenyl ketone), Irgacure®500 (1-hydroxycyclohexylphenyl ketone, benzophenone), and other photo-initiators of theIrgacure®-type available from Ciba-Geigy ; Darocur®-typephoto-initiators, available from Merck, benzophenone and the like.

Examples of optionally employed thermal initiators are known to thoseskilled in the art and include, among others, organic peroxides in theform of diacyl peroxides, peroxydicarbonates, alkyl peresters, dialkylperoxides, perketals, ketone peroxides and alkyl hydroperoxides.Specific examples of such thermal initiators are dibenzoyl peroxide,tert-butyl perbenzoate and azobisisobutyronitrile. These initiators areadded to the coating composition in amounts known to one skilled in theart. Typically the initiator will be added in an amount between 0.1 and2% by weight, based on the amount of crosslinking agent.

The compositions may further contain additives that provide the coatingwith additional properties, such as antimicrobial properties. Examplesinclude [C₁₈H₃₇N (CH₃)₂(CH₂)₃Si(OCH₃)₃]⁺Cl. However, the addition ofionic additives is preferably kept below about 10% by weight, in ordernot to adversely affect the water repellency properties of thecomposition.

The reaction product comprised in the composition of the presentinvention is obtainable by reacting components (A), (B), and optionally(C). Typically, the reaction product is a polycondensation product.Suitable reacting steps include at least partially condensation.

The polycondensation reaction is conveniently carried out by mixing thestarting components in an organic solvent preferably at roomtemperature, in the presence of sufficient water to effect hydrolysis ofthe hydrolysable groups. Preferably, the amount of water will be between0.1 and 20% by weight of the total composition, more preferably between1 and 10% by weight. In addition to water, an organic or inorganic acidor base catalyst should preferably be used.

It is preferred that the weight ratio of compounds (A) to compounds (B)in the preparation of the reaction product is 1:1 to 1:20 andparticularly preferred 1:1 to 1:10. The composition to prepare thereaction product comprises a substantial amount of component (B), i.e.an amount greater than a catalytic amount. Typically, component (B)comprises more than 10 weight percent and more preferably more than 25weight percent based on the total weight of the components used. In aparticularly preferred embodiment, component (B) comprises more than 50weight percent based on the total weight of the components used.Compound (C) can be used between 0 and 50%, preferably between 0 and 35%by weight, based on the total weight of the components used.

While the benefits of reacting components A and B (optionally with C)extend over a wide range of compositions, good initial repellency isachieved for coatings despite relatively low levels of thefluorochemical polyether silane (component A) involved in producing thereaction product. Therefore a preferred composition of this inventioncomprises the relatively expensive fluorosilane at 5-20% wt. %, givingan economic advantage to the compositions of this invention over otherfluorinated coatings. Additionally, compositions obtained from 5-20 wt.% component A were quite surprisingly more durable in maintainingrepellency after abrasion of a coated surface.

A homogeneous reaction mixture can be obtained by mixing the componentsin solvent, in the presence of water, and optionally an acid or basecatalyst. In particular, there is no need for a two step reaction, wherein a first step a precondensate of compound (B) is formed and in asecond step, the fluorochemical polyether disilane is added. Uponmixing, a homogenous mixture is obtained wherein substantially no phaseseparation occurs.

Organic acid catalysts include acetic acid, citric acid, formic acid,triflic acid, perfluorobutyric acid and the like. Examples of inorganicacids include sulphuric acid, hydrochloric acid and the like. Examplesof useful base catalysts include sodium hydroxide, potassium hydroxideand triethylamine. The acid or base catalyst will generally be used inamounts between about 0.01 and 10%, more preferably between 0.05 and 5%by weight of the total composition.

The composition of the present invention may include one or more organicsolvents. The organic solvent or blend of organic solvents used must becapable of dissolving a mixture of compounds (A), (B) and optionally (C)and the fluorinated polycondensate formed after reaction. Preferably,the organic solvent or blend of organic solvents used is capable ofdissolving at least 0.01% of the fluorochemical polycondensate.Furthermore, the solvent or mixture of solvents preferably has asolubility for water of at least 0.1%, preferably 1% by weight and asolubility for the acid or base catalyst of at least 0.01%, preferably0.1% by weight. If the organic solvent or mixture of organic solvents donot meet these criteria, it may not be possible to obtain a homogeneousmixture of the fluorinated polycondensate, solvent(s), water andcatalyst.

Suitable organic solvents, or mixtures of solvents can be selected fromaliphatic alcohols (preferably containing 1 to 6 carbon atoms), such asmethanol, ethanol, isopropylalcohol; ketones such as acetone or methylethyl ketone; esters, such as ethyl acetate, methylformate and ethers,such as diethyl ether. Particularly preferred solvents include ethanoland acetone.

Fluorinated solvents may be used in combination with the organicsolvents in order to improve solubility of the starting compounds and/orthe fluorochemical polycondensate. Such fluorinated solvents willgenerally not be suitable for use on their own because they willgenerally not meet the requirements of solubility for water and acid orbase unless they additionally contain hydrophilic groups such asCF₃CH₂OH.

Examples of fluorinated solvents include fluorinated hydrocarbons, suchas perfluorohexane or perfluorooctane, available from 3M; partiallyfluorinated hydrocarbons, such as pentafluorobutane, available fromSolvay, or CF₃CFHCFHCF₂CF₃, available from DuPont; hydrofluoroethers,such as methyl perfluorobutyl ether or ethyl perfluorobutyl ether,available from 3M. Various blends of these materials with organicsolvents can be used.

It will further be appreciated by one skilled in the art that thepreparation of fluorochemical polycondensates according to the presentinvention results in a mixture of compounds. A condensation sequence isdescribed by Arkles (CHEMTECH (1977), v. 7 pp 766-78).

The composition comprising the fluorinated polycondensates of thepresent invention is generally applied to the substrate in amountssufficient to produce a coating that is water and oil repellent. Thiscoating can be extremely thin, e.g. 1 to 50 molecular layers, though inpractice a useful coating may be thicker.

Suitable substrates that can be treated in a particularly effective waywith the fluorinated polycondensate mixture of this invention includesubstrates having a hard surface that preferably has groups capable ofreacting with the fluorinated polycondensate. Particularly preferredsubstrates include ceramics, glass, metal, natural and man-made stone,polymeric materials (such as poly(meth)acrylate, polycarbonate,polystyrene, styrene copolymers, such as styrene acrylonitrilecopolymers, polyesters, polyethylene terephthalate), paints (such asthose on acrylic resins), powder coatings (such as polyurethane orhybrid powder coatings), and wood. Various articles can be effectivelytreated with the fluorochemical solution of the present invention toprovide a water and oil repellent coating thereon. Examples includeceramic tiles, bathtubs or toilets, glass shower panels, constructionglass, various parts of a vehicle (such as the mirror or windscreen),glass, and ceramic or enamel pottery materials.

Treatment of the substrates results in rendering the treated surfacesless retentive of soil and more readily cleanable due to the oil andwater repellent nature of the treated surfaces. These desirableproperties are maintained despite extended exposure or use and repeatedcleanings because of the high degree of durability of the treatedsurface as can be obtained through the compositions of this invention.

To effect the treatment of a substrate, the fluorochemicalpolycondensate, preferably in the form of a solvent composition asdisclosed above, is applied to the substrate. The amount offluorochemical polycondensate to be coated on the substrate willgenerally be that amount sufficient to produce a coating which is waterand oil repellent, such a coating having at 20° C. a contact angle withdistilled water of at least 80°, and a contact angle with n-hexadecaneof at least 40°, measured after drying and curing of the coating.

Preferably, the substrate should be clean prior to applying thecompositions of the invention so as to obtain optimum characteristics,particularly durability. That is, the surface of the substrate to becoated should be substantially free of organic contamination prior tocoating. Cleaning techniques depend on the type of substrate andinclude, for example, a solvent washing step with an organic solvent,such as acetone or ethanol.

The coating composition is typically a relatively diluted solution,containing between 0.01 and 5 percent by weight of the fluorochemicalpolycondensate, more preferably, between 0.03 and 3 percent by weight ofthe fluorochemical polycondensate, and most preferably, between 0.05 and2 percent by weight of the fluorochemical polycondensate. In accordancewith a preferred embodiment, compositions for application to a substrateare prepared by diluting a concentrate comprising a solution of at least25% by weight of a fluorochemical polycondensate in an organic solvent,by adding to the concentrate an organic solvent or mixture of solvents.

A wide variety of coating methods can be used to apply a composition ofthe present invention, such as brushing, spraying, dipping, rolling,spreading, and the like. A preferred coating method for application of afluorochemical polycondensate of the present invention includes sprayapplication. A substrate to be coated can typically be contacted withthe treating composition at room temperature (typically, about 20° C. toabout 25° C). Alternatively, the mixture can be applied to substratesthat are preheated at a temperature of for example between 60° C. and150° C. This is of particular interest for industrial production, wheree.g. ceramic tiles can be treated immediately after the baking oven atthe end of the production line. Following application, the treatedsubstrate can be dried and cured at ambient or elevated temperature,e.g. at 40° to 300° C. and for a time sufficient to dry and cure.Alternatively, in addition with a thermal treatment, the coatingcomposition may be cured by irradiation (e.g. by means ofUV-irradiators, a laser, etc.) in a manner known per se, depending onthe type and presence, respectively of an initiator. The process mayalso require a polishing step to remove excess material.

Preferably, the obtained coating on the substrate is cured, generally atan elevated temperature of 40 to 300° C. This curing step can be done atthe beginning (application of the composition to a hot substrate) or atthe end of the application process. In an alternative method, thecoating can be cured by photochemical activation of materialsrepresented in formula (IV).

The following examples further illustrate the invention without theintention however to limit the invention thereto. All parts are byweight unless indicated otherwise.

1. Synthesis of Fluorinated Polyether Disilanes

A. Fluoropolyetherdisilane FES-1:

FES-1 was prepared by reacting perfluoropolyetherdiesterCH₃OC(O)CF₂O(CF₂O)₉₋₁₁(CF₂CF₂O)₉₋₁₁CF₂C(O)OCH₃ (with average molecularweight of about 2000), commercially available from Ausimont, Italy,under the trade designation Fomblin™ Z-DEAL, with3-aminopropyltrimethoxysilane, available from Aldrich Co., Milwaukee,Wis., as taught in U.S. Pat. No. 3,810,874 (Mitsch et al.), table 1,line 6. The exothermic reaction proceeded readily at room temperature,simply by mixing the starting materials. The progress of the reactionwas monitored by infrared analysis.

B. Hexafluoropropyleneoxide Diurethanedisilane FES-2:

FES-2 was prepared by reacting a perfluoropolyetherdiol(HOCH₂CF(CF₃)O(CF(CF₃)CF₂O)_(x)(CF₂)₄O(CF(CF₃)CF₂O)_(y)CF(CF₃)CH₂OH(with average molecular weight of about 1300; x+y is about 6-7) with twoequivalents of 3-trimethoxysilylpropylisocyanate in ethylacetate, at 80°C. during 16 hours under nitrogen atmosphere and in the presence ofdibutyltindilaurate. After the reaction was completed, as indicated byIR-analysis, the ethylacetate was evaporated.

C. Preparation of FES-3:

FES-3 was prepared by reacting Fomblin Z-DEAL with 2 equivalents ofbis(3-(trimethoxysilyl)propyl)amine,available from Aldrich, Milwaukee,Wis. as described in U.S. Pat. No. 3,810,874. The reaction was performedunder nitrogen atmosphere at 80° C. for 6 hrs. Reaction progressreaction was monitored by IR analysis.

D. Preparation of FES-4:

FES-4 was prepared by reacting a mixture of HFPO-oligomers with formulaCF3CF2CF20 (CF(CF3)CF20)n)CF(CF3)COOCH3 (with n˜5), with one equivalentof bis (3-(trimethoxysilyl)propyl)amine, available from Aldrich,Milwaukee, Wis. as described in U.S. Pat. No. 3,810,874. The reactionwas carried out under nitrogen at 80° C. for 6 hrs. Reaction progresswas monitored by gas chromatographic analysis.

2. Synthesis of Fluorochemical Polycondensate FESG-1

Several fluorochemical polycondensates as given in table 1 were preparedsimilar to the synthesis of FESG-1:

In a three-necked flask of 250 ml, fitted with a condenser, stirrer andthermometer, were placed 10 g of FES-1, 10 g TEOS (tetraethoxysilane;available from Aldrich Co., Milwaukee, Wis.), 20 g ethanol, 2.0 g DI—H₂Oand 1.0 g acetic acid. The clear mixture was stirred at room temperaturefor 16 hrs. Conversion of alkoxy silane groups was determined, aftersolvent evaporation, using infrared and C¹³—NMR analysis. Conversion wasabout 96%. The slightly hazy reaction mixture was then diluted to 0.1%fluorochemical solids in ethanol.

The preparation of the fluorochemical polycondensates FESG-5 and FESG-8were prepared in a similar manner to that noted above with the exceptionthat 0.1 g of DI—H₂O was added instead of 2.0 g of DI—H₂O.

TABLE 1 Composition of fluorochemical polycondensates FESG CompoundsWeight ratio FESG-1 FES-1/TEOS 1/1 FESG-2FES-1/TEOS/Octadecyltrimethoxysilane 2/2/1 FESG-3FES-1/TEOS/aminopropyltrimethoxysilane 2/2/1 FESG-4 FES-1/TEOS/ 10/10/1C₁₈H₃₇N⁺(CH₃)₂(CH₂)₃Si(OCH₃)₃Cl⁻I FESG-5 FES-1/tetraethoxyzirconate 1/1FESG-6 FES-1/TEOS/aminopropyltrimethoxysilane 1/1/1 FESG-7 FES-1/TEOS1/10 FESG-8 FES-1/tetraisopropyloxytitanate 1/1 FESG-9 FES-2/TEOS 1/1FESG-10 FES-2/TEOS/epoxypropyltrimethoxysilane 2/2/1 FESG-11 FES-3/TEOS1/1 FESG-12 FES-4/TEOS 1/1

Substrates

The fluorochemical polycondensate mixtures according to the inventionwere tested on various substrates as given below:

Substrate Supplier White glazed wall tiles Villeroy and Boch, GermanyPolymethylmethacrylate (PMMA) sheet NUDEC, Spain LinoleumForbo-Krommerie, Netherlands Enamel plate ROCA, Spain Epoxy powdercoating Ruhr Pulverlack GmbH, Germany Wood BRICO, Belgium Chromatedsteel Ideal Standard, Germany

Methods of Testing

Contact Angles

The treated substrates were tested for their contact angles versus water(W) and n-hexadecane (O) using an Olympus TGHM goniometer. The contactangles were measured before (initial) and directly after abrasion(abrasion), unless otherwise indicated. The values are the mean valuesof 4 measurements and are reported in degrees. The minimum measurablevalue for a contact angle was 20. A value <20 meant that the liquidspread on the surface.

Abrasion Test

The treated substrates were abraded using an AATCC Crockmeter, 20 cyclesusing sandpaper nr. 600 (available from 3M). Alternatively, abrasiontesting was accomplished using an Erichsen cleaning machine, 3M HighPerformance Cloth (available from 3M) and CIF cleaner (available fromLever), using 40 cycles.

EXAMPLES Examples 1 to 12 and Comparative Examples C-1 to C-3

In examples 1 to 12, 0.1% fluorochemical polycondensate mixturesprepared according to the general procedure, were sprayed onto whiteVilleroy & Boch tiles, kept at room temperature, followed by curing at150° C. during 30 minutes. After cooling to 50° C., excess product waspolished off with a paper wipe. Contact angles were measured before andafter abrasion with an Erichsen cleaning machine. Comparative exampleC-1 was made with a mixture of a fluorochemical silane composition(according to GB 2 218 097, example 25) and TEOS in a weight ratio 1/1.Comparative example C-2 was made with a mixture of Ausimont MF 407, aperfluoropolyether monosilane, available from Ausimont and TEOS in aratio weight 1/1. Comparative example C-3 was made with a mixture,prepared according to U.S. Pat. No. 6,054,601, example 1. The resultsare given in table 2.

TABLE 2 Contact angles of wall tiles treated with fluorochemicalpolycondensate mixtures. Contact angles (°) Initial After AfterFluorochemical Initial n- abrasion abrasion n- Ex polycondensates Waterhexadecane Water hexadecane 1 FESG-1 108 65 90 52 2 FESG-2 102 58 85 453 FESG-3 109 58 95 54 4 FESG-4 98 57 85 45 5 FESG-5 104 63 85 54 6FESG-6 105 60 85 47 7 FESG-7 105 60 92 55 8 FESG-8 100 60 85 52 9 FESG-9106 62 80 45 10 FESG-10 103 60 85 47 11 FESG-11 105 65 90 50 12 FESG-12100 58 80 45 C-1 GB 2 218097, 100 65 58 32 ex 25/TEOS 1/1 C-2 MF407/TEOS1/1 93 52 55 20 C-3 Example 1 in 95 50 50 20 U.S. Pat. No. 6,054,601

The results indicated that tiles with high oil- and water-repellencycould be made by using fluorochemical polycondensate compositionsaccording to the invention. High contact angles were measured,initially, but especially also after abrasion, indicating that highlydurable coatings were made. To the contrary, the comparative examplesdid not meet the requirements for oil and/or water repellency afterabrasion.

Examples 13 to 18

In examples 13 to 18, different substrates, which were kept at roomtemperature, were treated with FESG-1 by spray application. The treatedsubstrates were dried at 80° C. for 30 min. After cooling to 40° C., theexcess product was polished off using a paper wipe. Abrasion test wasdone using the AATCC Crockmeter. The contact angles of untreatedsubstrates were recorded as well as the contact angles of the treatedsubstrates, before and after abrasion. The results are given in table 3.

TABLE 3 Contact angles of substrates treated with fluorochemicalpolycondensate mixtures. Untreated FESG-1 initial FESG-1 initialAbrasion Ex Substrate W O W O W O 13 Linoleum 92 <20 120 60 108 55 14PMMA 70 <20 90 60 78 45 15 Epoxy 65 <20 92 62 85 55 16 Wood <20 <20 12056 65 43 17 Enamel 40 <20 96 58 90 50 18 Chromated steel 72 <20 95 60 8550

The results in table 3 show that the application of a 0.1% mixture offluorochemical polycondensate, according to the invention, improved thewater and oil repellency of the different substrates considerably. Inall cases, high durability of the treatment was observed.

What is claimed is:
 1. A composition comprising the reaction productobtainable after a substantially complete condensation reaction of: (A)at least one fluorochemical polyether silane compound the formula:R_(f)—[Q—CR₂—Si(Y)_(3−x)(R¹)_(x)]_(z) wherein R_(f) represents amultivalent polyfluoropolyether segment, Q represents an organicdivalent linking group, R¹ represents a C₁-C₈ alkyl group, Y representsa hydrolysable group, R represents hydrogen or an alkyl group of 1 to 4carbon atoms whereby the R groups may be the same or different, z is 2,3 or 4 and x is 0 or 1; and (B) a substantial amount of one or morenon-fluorinated compounds of an element M selected from the groupconsisting of Si, Ti, Zr, B, Al, Ge, V, Pb, Sn and Zn and having atleast two hydrolysable groups per molecule; wherein the hydrolysablegroups in components (A) and (B) may be the same or different and areindependently selected from a halide group, an alkoxy group, an acyloxygroup, an aryloxy group or a polyoxyalkylene group.
 2. A compositionaccording top claim 1 wherein said component (B) is a compound accordingto the formula: (R²)_(q)M(Y¹)_(p−q) wherein R² represents anon-hydrolysable group, M represents an element selected from the groupconsisting of Si, Ti, Zr, B, Al, Ge, V, Pb, Sn and Zn, p is 3 or 4depending on the valence of M, q is 0,1 or 2, and Y¹ represents ahydrolysable group.
 3. A composition according to claim 1 wherein saidreaction product is a reaction product obtainable from a substantiallycomplete condensation ration of said components (A) and (B) and furthera crosslinking agent (C).
 4. A composition according to claim 3 whereinthe crosslinking agent (C) is a compound of an element M¹ that isselected from the group consisting of Si, Ti, Zr, B, Al, Ge, V, Pb, Snand Zn, said crosslinking agent (C) further having at least onehydrolysable group and at least one reactive functional group permolecule that is capable of engaging in a crosslinking reaction.
 5. Thecomposition according to claim 1, wherein the polyfluropolyether segmentincludes perfluorinated repeating units selected from the groupconsisting of —(CF_(n)F_(2n)O)—, —(CF(Z)O)—, —(CF(Z)C_(n) F_(2n)O)—,—(C_(n)F_(2n)CF(Z)O)—, —CF₂CF(Z)O)—, and combinations thereof, wherein Zis a perfluoroalkyl group, an oxygen-substituted perfluoroalkyl group, aperfluoroalkoxy group, or an oxygen-substituted perfluoroalkoxy group,all of which can be linear, branched, or cyclic, and have 1 to 9 carbonatoms and 0 to 4 oxygen atoms and wherein n is a number from 1 to 12inclusive.
 6. The composition according to claim 1, wherein the weightratio of component (A) to component (B) is 1:1 to 1:20.
 7. A coatingcomposition comprising 0.01 to 5 weight percent of the composition ofclaim 1 and an organic solvent.
 8. A coated substrate comprising acoating derivable from the composition of claim
 1. 9. Method of treatinga substrate, comprising the steps of coating at least part of thesurface of said substrate with a coating composition as defined inclaim
 1. 10. Method according to claim 9 wherein said substrate isglass, ceramic, metal or a polymeric substrate.
 11. Method according toclaim 9 wherein said method further involves the step of subjecting thecoated substrate to an elevated temperature in the range of 40 to 400°C.
 12. The composition of claim 1, wherein Rf is selected from the groupconsisting of —CF₂O(CF₂O)_(m)(C₂F₄O)_(p)CF₂—,—CF(CF₃)—(OCF₂CF(CF₃))_(p)O—R_(f)′—O(CF(CF₃)CF₂O)_(p)CF(CF₃)—,—CF₂O(C₂F₄O)_(p)CF₂—, and —(CF₂)₃O(C₄F₈O)_(p)(CF₂)₃—, wherein R_(f)′ isa divalent, perfluoroalkyiene group containing one or more carbons andoptionally catenary O or N, m is 1 to 50, and p is 3 to
 40. 13. Aprocess for the preparation of a perfluoropolyether condensationproduct, the process comprising the steps of admixing components: (A) atleast one fluorochemical polyether silane compound the formula:R_(f)—[Q—CR₂—Si(Y)_(3−x)(R¹)_(x)]_(z) wherein R_(f) represents amultivalent polyfluoropolyether segment, Q represents an organicdivalent linking group, R¹ represents a C_(1-C) ₈ alkyl group, Yrepresents a hydrolysable group, R represents hydrogen or an alkyl groupof 1 to 4 carbon atoms whereby the R groups may be the same ordifferent, z is 2, 3 or 4 and x is 0 or 1; (B) a substantial amount ofone or more non-fluorinated compounds of an element M selected from thegroup consisting of Si, Ti, Zr, B, Al, Ge, V, Pb, Sn and Zn and havingat least two hydrolysable groups per molecule; and optionally (C) acrosslinking agent that is a compound of an element M¹ that is selectedfrom the group consisting of Si, Ti, Zr, B, Al, Ge, V, Pb, Sn and Zn,said crosslinking agent (C) further having at least one hydrolysablegroup and at least one reactive functional group per molecule that iscapable of engaging in a crosslinking reaction, wherein the hydrolysablegroups in components (A) and (B) and (C) may be the same or differentand are independently selected from a halide group, an alkoxy group, anacyloxy group, an aryloxy group or a polyoxyalkylene group; and reactingthe components until substantial completion of the reaction is detected.14. Process according to claim 13 wherein said components (A), (B) andoptionally (C) are further admixed with water and an acid or basecatalyst.